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<blockquote data-quote="Art Welter" data-source="post: 215687" data-attributes="member: 52">Vladimir,I could agree the &quot;Second amp is better&quot; (not exclusively in the low frequencies), but not because of it&#039;s damping factor, but because&nbsp; of the progressive power supply current limiting that takes place at the lower impedance.Low frequency response may exhibit more current limiting &quot;pumping&quot; due to impedance extremes and current demands, a &quot;four ohm&quot; cabinet may drop to 3.5 ohms at Fb (box tuning frequency), and be 20 to 40 ohms (or more) either side in just a 1/2 octave. An amp with no current limiting above 4 ohms, P4=P8x2 would have a &quot;Perfect Kd&quot; of 6222. This amp would&nbsp; tend to emit sparks and smoke if driving too low of an impedance when current exceeds the output devices capability.By your metric, an amp with a P8/P4 ratio lower than 500/906.66 fails the &quot;current limit suck&quot; test, coming in at 19.9.That type of amp will still sound OK at lower drive levels, just begins to suck when pushed beyond the current limits.That said, if the speaker cables are too long and thin, damping factor falls below 20, and speaker&#039;s transient response is reduced at any level, regardless of the amplifier&#039;s damping factor or current limiting.Art</blockquote>

[QUOTE="Art Welter, post: 215687, member: 52"] Vladimir, I could agree the "Second amp is better" (not exclusively in the low frequencies), but not because of it's damping factor, but because of the progressive power supply current limiting that takes place at the lower impedance. Low frequency response may exhibit more current limiting "pumping" due to impedance extremes and current demands, a "four ohm" cabinet may drop to 3.5 ohms at Fb (box tuning frequency), and be 20 to 40 ohms (or more) either side in just a 1/2 octave. An amp with no current limiting above 4 ohms, P4=P8x2 would have a "Perfect Kd" of 6222. This amp would tend to emit sparks and smoke if driving too low of an impedance when current exceeds the output devices capability. By your metric, an amp with a P8/P4 ratio lower than 500/906.66 fails the "current limit suck" test, coming in at 19.9. That type of amp will still sound OK at lower drive levels, just begins to suck when pushed beyond the current limits. That said, if the speaker cables are too long and thin, damping factor falls below 20, and speaker's transient response is reduced at any level, regardless of the amplifier's damping factor or current limiting. Art [/QUOTE]

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